JP2003178694A - Cathode-ray tube with damper wire support spring - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solution for a problem of weakening resonance vibration at a tensile force shadow mask and thus to prevent degradation of picture quality caused by external vibration and to provide a cathode-ray tube with a tensile force mask for color selection electrode attached to a support frame. <P>SOLUTION: The cathode-ray tube (10) has a mask (30) in a tensed state supported by the support frame (38). The tensile force mask is sensitive to vibration and adapted to be attached by tensile force in the cathode-ray tube. The tensile force mask is attached to the opposite side of a tensile force mask support frame and includes a damper wire support spring (60) extending therefrom. The damper wire support spring with an extensibility part (62) for supporting a damper wire (58) contacts and crosses a surface of the tensile force mask to weaken the vibration at the mask. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates generally to cathode ray tubes, and more particularly to improved means for damping vibrations in tubes having tension masks and the like.

[0002]

As is known in the art, cathode ray tubes include
It is typically composed of a glass envelope and includes an electron gun located within the neck portion of the envelope for generating and directing three electron beams on the screen of the tube. The screen is located on the inside surface of the front panel of the tube and consists of an array of three different color emitting phosphor elements. The color-selecting electrodes, either shadow masks or focus masks,
It is placed between the gun and the phosphor screen to allow each electron beam to strike only the emitter element with respect to the electron beam.

In a conventional color cathode ray tube having a two-dimensionally curved color-selective electrode or shadow mask, the curvature of the mask and the thickness of the mask make the cathode ray tube structurally uniquely supported. Another type of commercially available shadow mask is in tension with respect to the support frame and is not a unique support such as a two dimensional curved mold. Tension shadow masks include a plurality of vertically extending, very thin, parallel strands maintained at high tension. In another type of tension mask, the frame supporting the mask is designed to allow the mask to de-tension during heat treatment of the tube. The form of the cylindrical tension shadow mask described above is prone to vibration, as it may be caused, for example, by external mechanical rhythms or speakers for the television receiver. The resonant frequency of the vibration of the mask will change depending on the mechanical parameters of the mask and the tension of the mask. Any vibration of the mask causes landing of the electron beam out of position associated with each emitter element, causing color mixing in the reproduced image.

Various means have been proposed to reduce the above-mentioned resonance vibration. One example for dampening the vibration of a tension mask includes a damping wire stretched across the mask to dampen vibrations in the mask strands due to relative movement between the strand and the wire. The damping wire can be held against the mask strands due to the curved shape of the mask. The ends of the wire are secured to the frame that supports the tension mask by tabs that hold the wire under light tension. With such an arrangement, the strands will be elastically pushed by the wire and thus will not vibrate due to external mechanical or electron beam impact. An inherent drawback of this type of mask assembly is the variation in the height of the tabs that causes any of the wires that do not touch or push the strands causing significant deflection of the strands to prevent weakening the movement of the mask. including. The problem is exacerbated by the use of a tension mask having a particular tension distribution across the mask, or by the use of a de-tensioned mask frame which results in a relatively weak strand stretching force.

[0005]

SUMMARY OF THE INVENTION The present invention aims to provide a solution to the problem of dampening resonant vibrations in tension shadow masks, and therefore aims to prevent the deterioration of image quality caused by external vibrations. To do.

[0006]

SUMMARY OF THE INVENTION The present invention provides a cathode ray tube having a tension mask of color selective electrodes attached to a support frame. The tension mask includes a damper wire support spring applied to and extending from the tension mask support frame on the opposite side. The damper wire support spring has an extensible portion that supports the damper wire in contact with the mask and crosses the surface of the tension mask to dampen the vibration of the mask.

Further features and advantages of the invention may be best understood by referring to the following details of the preferred embodiments obtained by the invention in connection with the accompanying drawings. Like reference numerals in the accompanying drawings indicate like elements.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT FIG. 1 shows a rectangular front panel 1.
Shown is a color picture tube 10 having a tubular neck 16 connected by a rectangular funnel 18 with a glass envelope 12 containing 4. The funnel 18 has an internal conductive coating (not shown) extending from the anode button 20 to the wide portion of the funnel and the neck 16. The panel 14 includes a peripheral flange or sidewall 24 that is sealed to the funnel 18 by a substantially horizontal exterior viewing faceplate 22 and a glass frit 26.
including. The three-color light emitter screen 28 is held by the inner surface of the front plate 22. Screen 28 is a line screen with phosphor lines arranged in three structures, each tristructure containing each phosphor line of three colors. A color selection electrode or tension shadow mask 30 was movably attached to the screen 28 in a predetermined spaced relationship. The electron gun 32, shown schematically in phantom in FIG. 1, produces three in-line electron beams 34, a central beam and two lateral beams along a focusing path through the mask 30 towards the screen 28, And it was mounted centrally within the neck 16 for guiding.

The tube 10 is designed for use with an external magnetic deflection yoke, such as the yoke 36 shown near the funnel-neck connection. When activated, the yoke 36
Receives a magnetic field for the three beams, which causes the beam to scan horizontally and vertically in a rectangular raster across the screen 28.

FIG. 2 is a perspective view of the tension mask 30 attached to the frame 38. Tension mask 30 includes two long sides 40 and 42 and two short sides 44 and 46. The two long sides 40 and 42 of the tension mask are parallel to the central major axis X of the tube and the two short sides 44 and 46 are
Is parallel to the minor axis Y of the tube. Tension mask 3
0 includes an active interstitial portion 48 that includes a plurality of vertically extending parallel strands 50. Strand 50
A number of elongated gaps 52 in between are parallel to the minor axis Y of the tube. The electron beam passes through the gap 52 in the gap 48 that is active during operation of the tube.

Frame 38 includes four sides, two long sides 54 substantially parallel to the major axis X of the tube and two short sides 56 parallel to the minor axis Y of the tube. The damper wire 58 is a tension shadow mask 30 perpendicular to the gap 52.
Extend across. Damper wire support spring 6
0 is fixed to and extends from the short side 56 of the frame 38 in the peripheral portion outside the tension shadow mask 30. The damper wire support spring 60 includes an extensible portion that supports a damper wire 58 on the screen side of the tension shadow mask 30 that contacts the strands 50 of the tension shadow mask 30 to dampen vibrations in the mask.

FIG. 3 is a diagram of a damper wire support spring 60 for a tension mask according to the present invention. The damper wire support spring 60 includes a retaining element 64 for securing the damper wire support spring 60 to the short side 56 of the frame 38 and an extensible portion 62 for supporting the damper wire 58 in contact with the strands 50.
(As shown in FIG. 2). The extensible portion 62 is
A relatively thin spring element 66 fixed to the free end of the retaining element 64. The spring element 66 extends from the free end of the retaining element 64 and bends inwards (as shown in FIG. 2) in a deflected position towards the central active clearance portion 48 of the tension shadow mask 30. The damper wire 58 is
It is attached to the spring element 66, for example by spot welding, so that the damper wire 58 is allowed to have a degree of "play" or movement, referred to herein as "extendability", depending on the mask preloading or sideloading forces. In addition, it is held between the damper wire support spring 60 and the strand 50. It will be appreciated that as long as the damper wire 58 is supported by the extensible portion 62, the damper wire 58 may also be attached to the retaining element 64, for example by spot welding.

The damper wire support spring 60 is manufactured by separately forming the retaining element 64 and the spring element 66 and then mating with each other so that the size of each part is dependent on the required extensibility. Therefore, it is set individually. In the preferred embodiment, the spring element 66 provides the extensibility of the damper wire 58 in a direction perpendicular to the XY plane of the mask or tube, as well as in the direction tangential to the surface of the tension shadow mask 30. To allow, thickness in the range of about 0.001 to 0.003 inches (0.25 to 0.76 mm) and about 0.0
It consists of a suitable material having a width of 5 to 0.20 inches (12.7 to 50.8 mm). It will be appreciated that the spring element 66 may be constructed in alternative scales, if desired.

FIG. 4 is a depiction of another alternative embodiment of the present invention. In this embodiment, a damper wire support spring 60 that supports the damper wire 58.
The extensible portion 62 of is a unitary structure with an L-shaped portion having a cut region 68. The damper wire support spring 60 is formed of a single sheet of material and has a cutting area 68.
Are introduced with the extensibility of the damper wire 58 being substantially the same as achieved by the embodiment shown in FIG. However, with the cutting area 68, the damper wire 58 is not supported by the curved profile and spring deflection of the spring element 66 as shown in FIG. 3, but due to the extensibility the damper wire support spring 60. Work to apply preload force to the free end of. In either embodiment, the extensibility of the damper wire support spring 60 is such that the damper wire is more or less flexible across the mask such that the damper wire is more or less free to move in response to forces associated with deflection and tension distribution changes at the mask. Fix the damper wire to 50.

According to the invention, the extensibility provided by the vibration damping means is the result of heating and cooling of the mask,
Or, it maintains the effectiveness of the damper wire despite significant changes in the resonant frequency of the tension mask, which may be the result of mechanical shocks external to the tube. The damper wire support springs 60 maintain the damper wire 58 to maintain contact with the strands 50 even if the tension distribution across the mask is relatively weak due to the stretching force of the strands.
Provides extensibility in the. As a result, deterioration of image quality caused by external vibration or thermal cycling can be prevented.

While the invention has been described with respect to one or more specific embodiments, those skilled in the art will recognize that many modifications can be made without departing from the spirit and scope of the invention. For example, the number of damper wire support springs 60 may provide sufficient weakening of the tension mask,
Increased to support additional damper wires. Each embodiment and its obvious variations are considered to be within the spirit and scope of the claimed invention as claimed.

[Brief description of drawings]

FIG. 1 is a partial top view of a shaft portion of a color picture tube embodying the present invention.

FIG. 2 is a perspective view showing an embodiment of a damper wire support spring and a support frame in a tension mask according to the present invention.

FIG. 3 is a detailed perspective view of an exemplary damper wire support spring according to the present invention.

4 is a view similar to FIG. 3, depicting an alternative embodiment of a damper wire support spring.

[Explanation of symbols]

10 cathode ray tube 12 glass packets 14 Front panel 16 neck 18 funnel 20 Anode button 22 Front plate seen from outside 24 Flange or side wall around 26 glass frit 28 3-color luminescent screen 30 tension shadow mask 32 electron gun 34 electron beam 36 York 38 frames 40 long side 42 long side 44 short side 46 short side 48 Active gaps 50 strands 52 Gap 54 long side 56 short side 58 damper wire 60 damper wire support spring 62 Extensible part 64 elements to hold 66 Spring element 68 cutting area X spindle Y secondary axis

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Frank Rowland La Grande, Ju             near             United States California             93446 Paso Robles Country C             Love Drive 1529 F-term (reference) 5C031 EE01

Claims (9)

[Claims] 1. A cathode ray tube (10) having a tension mask (30) attached to a support frame (38) mounted in a cathode ray tube, the tension mask being attached to an opposite side of the support frame. And extends from the opposite side of the support frame and further includes a compliant portion (6
2) Damper wire support spring containing (60)
And a damper wire (58) supported by the extensible portion of the damper wire support spring for contacting the surface of the tension mask. 2. The damper wire support spring is fixed to the opposite side of the support frame and includes a retaining element (64) extending from the opposite side of the support frame and supporting the extensible portion. A cathode ray tube as defined in claim 1. 3. Cathode ray tube as defined in claim 2, characterized in that the extensible part is a spring element (66) fixed to the free end of the retaining element. 4. The damper wire support spring comprises:
Cathode ray tube as defined in claim 1, characterized in that it is of unitary construction with a cutting area (68) accommodating the extensibility of the extensibility part. 5. A cathode ray tube (10) having a tension mask (30) attached to a support frame (38) mounted on a front plate (22) in the cathode ray tube, the tension mask comprising a screen side and an electronic side. Having a gun (32) side, the tensioning mask comprises a plurality of vertically extending parallels between the elongated gaps (52) caused by the passage of the electron beam (34) during operation of the tube. An active interstitial portion (48) formed by strands (50) of said support frame and two opposite borders of said support frame outside said active portion and from said two opposite borders. Supported by a damper wire support spring (60) extending and each further including an extensible portion (62), and the extensible portion to the screen side of the tension mask. Cathode ray tube, characterized in that it contains a damper wire (58) extending between said screen side and the extensibility moiety. 6. The damper wire support spring includes a retaining element (64) secured to the opposite side of the interface and extending from the opposite side of the interface to support the extensible section. A cathode ray tube as defined in claim 5. 7. The extensible portion is a spring element (66) secured to the retaining element and extends inwardly in a deflected position towards the active clearance portion. A cathode ray tube as defined in 6. 8. A cathode ray tube as defined in claim 7, wherein the spring element and the retaining element are extensible with respect to each other. 9. The damper wire support spring comprises:
Cathode ray tube as defined in claim 5, characterized in that it is of unitary construction with a cutting area (68) accommodating the extensibility of the extensibility part.